ES2325102T3 - APPARATUS FOR OSEA FIXATION. - Google Patents

Abstract

Apparatus for fixing a pair of broken bone pieces (12, 13), broken along a fracture line (11) of a bone (10) comprising: a resilient means (16); a first fastening means (15) located in one of said bone pieces; a second fastening means (17) located in the other bone piece; said resilient means (16) that interconnects the first and second anchoring means (15, 17), whereby a compressive force is applied through the fracture line characterized by an additional clamping means, and a second resilient means fixed to said additional fixing means located on the diametrically opposite side of said broken bone pieces that look at said first and second fastening means and the resilient means.

Description

Bone fixation apparatus.

Foundation of the invention Field of the Invention

The present invention relates to fixation. that is; and more particularly, to the apparatus for repairing fractures bone.

Model or type of related device

Several surgical plates have been used in the treatment of trauma to the facial or cranial bone structure, plastic surgery, reconstructive facial surgery and similar for keep the sections or bone fragments in place during The healing process. The surgical plates are placed facing the surface of bone sections that must be maintained together and fixed to the bone by grips or mechanical seals such as bone screws, wire sutures or other closures that fix the plate to the bone surface. The closures are embedded or well they press on the bone to prevent the plates Surgical be displaced from the surface of the sections bone. American patents nr. 4,966,599 and 5,290,281 show examples of bone stabilization plates that attach to the bone structure, for example, to the facial or cranial bones, by bone screws. The American patent nr. 4,655,203 reports on a surgical device for the immobilization of a bone fracture that includes a rigid plate and elements of hard fixing that can be inserted into the slots created in the bone.

Therefore, the current methods for bone fixation are:

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Plates bone

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Wire tensioners

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Screws

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Nails intramedullary

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Cerclages (junction wraps: nylon, metal or wire)

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External fixation (nails and frame)

All these outdated methods are basically different and each seems to be the method chosen for certain types of fractures There is also considerable agreement on indications and contraindications regarding when each one.

Bone plaque achieves compression of the fragments through a wedge geometry of the groove in the which screw is inserted. As the screw is tightened, the wedge geometry of the groove forces the plate into place correct while the bone fragments are arranged. The amount of compression depends on many variables; access to the place or center surgical, bone adjustment to the plate and the precision with which The screws are placed in the holes. The distribution of Compressive forces take place around the plate. I mean is most likely the plate has six to eight screws.

The surgical procedure requires skill; the plate should be profiled to the bone and the holes should be accurately perforated for reduction and compression adequate.

An undesirable consequence of bone plaque is the fact that after a short time, the flow of tension in the bone becoming a tension screen that weaken the bone As a result it is normally removed. The bone plaque can also produce a pressure necrosis in the bone and in the periosteum. This promotes the formation of adhesions between the sliding planes and can cause irritation type bag. As a result, bone plaque can interfere with rehabilitation and should be removed when they no longer represent no benefit See Uhthoff, H.K., and Dubc, F.L. (1979): "Changes in the bone structure in the dog under internal fixation rigid "Clinical Orthrop. Rel. Res., 81: 165-170 and Uhthoff, H.K., and Finnegan, M. (1983): "The effects of plaques metal in post-traumatic remodeling and bone mass "J. Bone Joint Surg., 1983 65-B; 66-71.

The wire used to maintain the bone fragments together are usually passed through the perforated holes, a loop is made and tied. Nothing turns out practical that the metal wire compresses the bone. For this the Wire should be stretched like an elastic band. But this is really an impractical application of the wire since its Elongation is a tiny percentage of the length. That is to say, due to the relative forces of the wire with respect to the bone, the bone will always fail in its performance before the wire metallic stretch. Using the wire as a tensioner equals that the wire can hold the bone fragments at a distance next and can eliminate stress loads but cannot apply An active form of compression to the fragments.

The screws (screwing screw) properly used work only in special cases in  that the break overlaps sufficiently so that the screw cross both bone walls. Screws add compression in that direction only (transverse) and not axially where it can Be the most beneficial. The screws can be used in pulverized fractures but only under conditions specific.

The strips or cerclage strips surrounding the bone work again only in ideal cases in which the breakage provides enough overlap. Like the screws, they work only in circumferential compression (no compression axial).

Intramedullary nails are used basically in the long bones of the body like the femur. Be inserted into the femur above and just inside the greater trochanter and into the intramedullary canal. Currently, all the world agrees that a procedure known as the nail intramedullary of Kuntscher, complemented with a design of interlocking or closing, is the treatment to choose for essentially all closed fractures of the femur between the lesser trochanter and the femoral condyles, regardless of fracture or spray grade model.

The external fixation consists of rods of large diameter wire running through the limb or bone completely. Normally 4, 6 or 8 wires cross the member to keep fractured bones in place. The External fixation is basically used for serious fractures, probably pulverized, where access to the fracture site is compromised and / or the orientation of the fragments quite hard. Frequently used with severe open fractures and a considerable soft tissue injury. The patient must endure a very uncomfortable and bulky device for a long time. There is also a risk of infection while being installing.

Therefore there is a need for a process to keep bone fragments well together while allowing a small amount of variability in the load that stimulates the bone regenaration.

The document US-A-5108397 shows an apparatus for stabilization of pelvic fractures, in particular the vertical double fractures. The apparatus comprises a plate and a rod that applies a rigid compression through the wings of the ílio and through the sacrum, as well as a screw and a cable that apply a non-rigid compression through the pubic symphysis in previous sense.

The document FR-A-2721818 shows an element of osteosynthesis consisting of a support (1), an elastic brace (2) and a tensioner and closure (3). One end of the tie is attached to the clamping while the other receives the tensioner and closes once has passed through the holes drilled in two fragments bone. The fastener is fixed to the outer surface of a fragment bone and tensioner / close to each other. The fastener can have the shape of a hook. Both the clamp and the tensioner / closure are of a metal or metal alloy such as titanium, steel or chrome-cobalt, either of a bone or non-bone material resorbable

WO-A / 99/35973 reveals a system to close a first side of a bone sectioned with a second lateral of a bone sectioned of a patient. The system includes a first clamping mechanism that adapts to enter the first side of the bone. Said first clamping mechanism comprises a housing that has a first opening that extends through the housing. The system it also comprises a second clamping mechanism that adapts to be fixed to the second side of the bone. The second mechanism it comprises a housing that has a second opening that is extends through the housing. The second mechanism is far and separated from the first clamping mechanism. The system too comprises a tie that extends through the first opening of the first clamping mechanism and the second opening of the second clamping mechanism that joins the first side of the bone sectioned with the second side of the sectioned bone.

Summary of the Invention

An objective of this invention is to achieve a apparatus that holds the bone fragments well together and allows a Small load variability that stimulates bone regeneration.

Another objective of this invention is to achieve a apparatus for a bone fixation process that promotes healing premature bone and hold the patient's joints and allow to move during the repair process, reducing with It is the period of therapy.

These and other objectives are met preferably with a bone fixation apparatus having the features disclosed in claim 1. The Dependent claims highlight the advantageous forms of the configuration of the present invention.

Brief description of the figures

Fig. 1 is an elevation view of an apparatus for the present invention used to fix at least two parts of a broken or crushed bone structure to advance the process of healing;

Fig. 2 is a cross-sectional view through the Figure 1;

Fig. 3 is a view similar to that of figure 1 which shows an alternative apparatus;

Fig. 4 is a cross-sectional view through the figure 3; Y

Fig. 5 is a view similar to Figure 1 of Another configuration of the invention.

Description of the preferred configuration

With respect to figure 1 of the drawing, shows a bone 10 that has a fracture line 11 that fractures completely bone 10 in 2 separate pieces, 12, 13. A first arrangement 14 of nails and a flexible line are arranged in a lateral bone 10 expanding the fracture line 11. By consequently, a first nail 15 is fixed to the bone piece 12 located at a predetermined distance, such as 8 mm, from the line of fracture 11. A line 16 of flexible material is fixed to nail 15 in an appropriate manner and leads to a second nail 17, fixed to the bone piece 13, at a predetermined distance of 8 mm, from the fracture line 11 on the other side of it. Line 16 that Wrap the nail 17 eliminates that tension applied. Line 16 It is now extended and wrapping a third nail 18, fixed to the bone piece 12, that is to say at a distance Default fracture line 11, such as 8 mm. The nail 18 it can be found approximately 10 mm or so from nail 20. Line 16 tightens again between nails 17 and 18 and then it extends to a fourth nail 19, is fixed in the bone piece 13 a a predetermined distance from fracture line 11, and about 10 mm from nail 17 and about 8 mm from line 11 and rolled around nail 19 and tense. Then line 16 extends from turn to the first nail 15, it is placed under tension and rolled around nail 15. Lines or tapes can be used 16 different if desired.

Line 16 can now be fixed to nail 15 or well it spreads again under a tension, back around the nail 17, over nail 18 and back to nail 19 and fixed there as shown in figure 1.

As can be seen in figure 2, a 100 identical arrangement of nails and flexible line in the lateral bone 10 diametrically opposite to arrangement 14 and not More illustrations are required.

Although nails have been shown that can get into bone 10 in some appropriate way, other elements  as the screws can also be used with line 16 wrapped in some way under the nail or screw head as appropriate. That is, as you can see in the Figure 3 in which related numerals refer to parts related to the arrangement of figure 1, instead of nails or screws or the like, an arrangement 200 having a plurality of holes or spaced holes, such as holes 20 to 23 (corresponding to nails 15, 17, 18, 19, respectively, and a its spacing from line 11) can be perforated or molded in some way in bone pieces 12, 13. Similar holes 20 ', 21 ', 22' and 23 'are formed in front of holes 20 to 23 (see fig. 4). Therefore line 16 begins at hole 22 (fixed therein appropriately, like an elongated knot), then extends to the hole 22 'on the opposite side of the bone 10 (fig. 4) using a needle or something similar, going through hole 23 'and leaving the hole 23 back to hole 20, etc., in the same way as in the Figure 1. As you can see in Figure 5, where again similar numerals refer to equal parts of the invention, only 3 nails 15, 17 and 18 are used with the line 16 that extends between them as mentioned before.

It can be seen that the best method for Bone healing promotion involves placing the bone fracture fragments in a rigid reduction and accurate.

The concern is not only for the expedited repair of bone fracture but for the effects deleterious in muscle, tendons, ligaments and joints.

Specifying, there are three stages or phases for the Fracture healing process. The first is the break or properly the energy failure and the meeting of the fragments bone. The second stage is called the inflammation period. This period of time goes from zero to five days depending on the possibility of infection, instability and trauma.

The third stage is the repair stage that It comprises approximately from the fourth day to about 40 days. This It is the period of hard and soft callus formation. The callus is a new tissue that forms in and around the fracture area to join the fragments for healing. Stabilize the zone of breakage so that the bone can begin to grow. The phase final is the remodeling stage, which starts at three to four weeks and continue until the fragments are firmly attached To the new bone. The fracture area is healed from the clinical point of view and according to the radiography. The average time in a adult is three to four months for the main long bones using a conventional treatment medium.

There are three requirements for remodeling Harvesian (from the bone) through the fracture zone: a) exact reduction (axial alignment), b) stable fixation, and c) Enough blood supply. That is a critical phase of the Fracture healing involves the formation of a bone bridge intact among the fragments. Because this implies union of the hard tissue, it turns out that the entire system must be immobilized At least momentarily. At this stage of healing, the ineffective immobilization of the fracture can lead to disunity hypertropic This occurs due to tissue persistence. fibrous or fibrous transformation of the corpus callosum osteogenic between the borders of the external callus. There is a small window for interfragmentary movement allowed and the use of fixation flexibility as a method for callus stimulation at this stage would be difficult when the path of fracture healing has already been assigned to certain conditions Biological and mechanical Finally, the rigid immobilization of the Fracture can short circuit this healing process. If I dont know get the rigid immobilization of a fracture, repair the fracture will basically be a primary callus and a response external bridge type. See Heppenstall, R.Bruce, "fracture Treatment and Healing "W.B. Sanders Co., Philadelphia 1980. With the rigid immobilization that form is removed and the fracture is healed thanks to the medullary callus and basic cortical healing.

There is great evidence that the bone immobilized and compression bone shorten normal physiology of healing. It seems that the ideal environment for healing is created keeping bone fragments close together, while allowing a minimum amount of load variability, which stimulates the bone regeneration A basic signal of bone growth is the electric potential. In normal activity, the bone leaves remodeling it under external tension, always creating bone new to handle compression forces. Use an effect piezoelectric to generate an electrical potential for this signal. See Brighton, Carl T, "Biophysics of Fracture Healing" and "Fracture Treatment & Healing" edited by R. Bruce Heppenstall 1980. Martin, R.B., "Theoretical analysis of the piezoelectric effect in bone "Journal of Biomechanics 12 55-63 1979, and Yasuda, I., "Piezoelectricity of Living Bone "J. Kyoto Pref. Univ.Med. (1953) 53: 325.

An electropositive potential on the side of the stressed bone and an electronegative potential on the side compressed. The electropositive signal triggers or causes resorption bone (tensioned side) and the electronegative signal triggers the bone growth (compression). This electrical potential generated by the tension increases when the bone is compressed and does not depend on the cell viability Research has also shown that the electrical signal comes from the organic component of the bone and not from the mineral component "That means that even if the bone is totally descaled, these signals generated by stress".

This invention puts into practice this bone physiology to promote premature bone healing and to maintain mobile joints thus reducing the time of treatment. A bone fracture is reduced and kept compressed by means of elastic tensioning strips or tapes. The tape can be of any suitable soft elastomer capable of placing a load Default compression over the entire fracture area.

Although an 8 mm spacing has been suggested, the first two nails can be found at approximately 7-10 mm from the proximal end of the fracture by a side and 10 mm from the end of the distal fragment on the other side. The fracture is reduced and an elastic strip is fixed between the two First nails with a fixed amount of tension. Although in the line 16 a single elastic strip has been arranged can be used separate lines or strips. Therefore, a group of nails 22, 23 with an additional strip or tape will be arranged in parallel to the two first nails 20, 21 at a distance of about 10 mm. This pair of tapes or tension strips or a single strip is now doubled diametrically in front of the first pair of nails 20, 21 to complete the fixation These distance dimensions and the sizes of the Nail / elastomer will vary with bone size.

There may be many modifications of this basic layout; in addition to adjusting the tapes or tension strips parallel to the bone axis as described, it is also can be placed in a diagonal arrangement for greater resistance to fracture torsion.

The goal is to reduce bone fracture with a sufficiently high compression to keep it in its site (complete stability) using fracture compression to promote premature bone healing and to contribute sufficient fixation that allows early mobility of the member.

The concept can be applied to fractures sprayed and can also be used in conjunction with a plate bone, an intramedullary rod or another fixation system where the tension in the strips or tapes is adjusted up or down to maintain the position of the bone fragments.

Any instrument can be used appropriate, such as manually operated devices that they work like a basic shotgun with a correction setting elastomer manual to a micro screwdriver  more complex motorized with an automatic sequencer for the adjustment and installation of the tapes on line 16.

The combination of tensioned bands or tapes 16 and nails provides a reduced, stable stable fracture compressed to promote rapid healing and provide enough structural integrity allowing movement of the member.

In a study that appears in "Improved Fracture Healing with less rigid plates "by A. Foux et al., Clinical Orthopedics and Related Research, No. 339, pp. 232-245, dated June 1997, the authors reported on page 239 that their essays indicated that the placement of bone fragments under compression resulted in recovery times much faster than Conventional bone repair procedures. The apparatus of This invention, when used to repair bone fragments, gives place at fast recovery times.

Claims (9)

1. Apparatus for fixing a pair of bone pieces broken (12, 13), broken along a fracture line (11) of a bone (10) comprising: a resilient medium (16); a first fastening means (15) located in a of said bone pieces; a second fastening means (17) located in the another bone piece; said resilient means (16) that interconnects the first and second anchoring means (15, 17), whereby a compressive force is applied through the fracture line characterized by an additional clamping means, and a second resilient means fixed to said additional fixation means located on the diametrically opposite side of said broken bone pieces that look at said first and second fastening means and the resilient means. 2. The apparatus of claim 1, wherein said first and second clamping means (15, 17) line up one with another, so the resilient medium (16) applies a force of active compression continued along one direction transverse to the fracture line. The apparatus of claim 1, characterized in that a third fastening means (18) placed adjacent to and on the same side as said first fastening means (15); a fourth clamping means (19) located adjacent and on the same side as said second clamping means (17), and said resilient medium (16) that interconnects the second clamping means with the third clamping means and the first means clamping with the fourth clamping means and the third clamping means clamping with the fourth clamping means; Y an additional clamping means and a second resilient means coupled to said additional clamping means adapted to be fixed on the diametrically opposite side of said broken bone pieces that look at said first, second, third, fourth anchoring means (15, 17, 18, 19) and said resilient means (16). 4. The apparatus of claim 1 or 3, characterized in that said first and second fastening means is a nail. 5. The apparatus of claim 1 or 3, characterized in that said first and second fastening means is a hole. 6. The apparatus of claim 5, characterized in that said hole extends through said bone pieces and said resilient means passes through said holes. 7. The apparatus in claim 1, characterized in that said resilient means (16) is an elastomeric branch. 8. The apparatus of claim 7, characterized in that said elastomeric branch includes double branches. 9. The apparatus of any one of claims 3 to 8, characterized in that the resilient means between the first and fourth clamping means (15, 19) and between the second and third clamping means (18, 17) cross to form an X; and because a second bone repair arrangement identical to the first bone repair provision is formed on the diametrically opposite side of said first bone repair arrangement.